The ultimate Aquaponics filter. It has many essential elements in this elaborate design. Look at all the innovative elements, especially the fish centrifuge. That will get the solids out of those little critters whether they like it or not!
There are three clearly defined approaches to what we know as Aquaponics.
1 Aquaculture with some plants hooked onto the end to help with Nitrate control.
2 Hydroponics with a few fish thrown into a tank to reduce the cost of nutrients.
3 Aquaponics as an ECO system, producing wonderful chemical free, clean food in a ecologically sensitive way combining the fish and plants lending both elements equal respect and importance.
Some who approach Aquaponics from the Aquaculture perspective want to get the ultimate filter. They have been led to believe that the more elaborate or the sheer quantity and size of the filter, the better their system will run. That is certainly true if running an Aquaculture system. Aquaculture methodologies are well established.
The idea of adding various gadgets to a system is very appealing to the “tinkerer” that lurks just below the surface in many a bloke. But just how much and what type is needed? Do we really need to filter or not?
There is just no doubt that there needs to be mechanical and biological filtration in any Aquaponics system. The fish in the system produce waste and it has to be dealt with in order for the fish to be happy and healthy.
In a home Aquaponics system the most efficient and convenient filter system is the humble media bed. Various designs have been put forward for a media bed and most of them work rather well, some better than others, but the differences in performance are usually not all that great.
Media beds, particularly gravel of 20mm (¾”) work exceptionally well. The humble media bed functions as a biological filter and a mechanical filter. It both converts the ammonia produced by the fish waste into useful nitrates which is plant food, and collects the solid material produces by the fish.. Further, in time it also functions extremely well in providing mineralisation of organic material thereby releasing mineral, and myriads of trace elements that one would expect to find in a well found organic garden.
If you run a domestic style AP system with enough grow beds attached, which, in my opinion is how a domestic system should be configured, then you do not need additional mechanical filtration. This is assuming that you are running a balanced system, that is, a system that is not overly loaded with fish and is in balance with the fish and plant occupancy.
More media filters means more vegetables can be grown. More media filters means more fish can be raised.
A really good way to build a very effective media filter is as follows.
Make a solid structure, possibly out of plywood and timber and line it with an appropriate liner. If a poly or fibreglass tank near that size can be found it would be ideal for the purpose.
A suggested good size is 2m long x 1m wide by 0.3 deep. (6’ x 3’x 1’deep)
Fill with gravel of 20mm or 3/4" (make sure it does not contain limestone.)
Pass the water of your system directly through this wonderful filter. Various methods can be employed to do this; a constant flow or flood and drain. Various plumbing and pumping regimes can be employed to regulate and distribute the water.
I have been using this style of filter for many years. They work exceptionally well, requiring little cleaning and minimal maintenance.
I have also discovered that worms will take up residence in this filter system..... Wonderful stuff. We all know what worms do for any garden. They are particularly important in an Aquaponics garden, processing solid organic material and releasing a myriad of minerals, and micro nutrients. The worms also play a vital role in the maintenance of the filter by reducing the volume of collected solids by up to 80%. The plants do really well, because, amongst other things, the action of the worms releases and makes available nutrients for these plants.
Much to my utter amazement I have found that , by growing plants in the top of this filter (I grow veggie types of plants) the efficiency of the filter is further enhanced. By growing plants in the filter I found that the Nitrates that are naturally produced by this very effective bio and mechanical filter, are used up by the plants. This wonderful little benefit means that I do not need to discard water on a regular basis to keep Nitrates under control. (Discarding water to lower Nitrate levels is common practice in aquaculture systems.)
I know this all sounds very unscientific.....but hey....it works and works astonishingly well.!
I have been running such systems now for more than 6 years, sold and installed hundreds of kits across Australia and also into the USA, NZ and China. My kits and that of the other only credible kit manufacturer in Australia, are highly successful. Clients enjoy a very high degree of satisfaction and enjoyment. Further to that there are literally tens of thousands of DIY system builds around the world using the humble media bed filter with excellent results. As far as we are able to tell we believe there are over one thousand Toteponics systems built from my plans utilising CHOP 2 methodology.
I am totally confident in what I say based on solid verifiable experience.
There are those who promote adding mechanical filters way beyond the humble media bed. These folk are actually trying to push fish production way beyond what a home based Aquaponics system should. This is actually home Aquaculture.
If you want to go outside that balance and push for more fish production and actually turn your AP system into a half baked Aquaculture system, then you need to start adding aquaculture like equipment such as moving bed filters, swirl filters and so on.
By going in the aquaculture direction, the beauty of the simplicity of a well balanced Aquaponics system is lost and it becomes ever more complicated to maintain and run.
This may be the deliberate choice of some operators of home systems.
If you want to add filters, then go for it....have fun....knock yourself out, add a couple, or three.
Some people that go on and on about filtration, are heavily influenced by Aquaculture people and have a strong aquaculture bent. They have lost sight of the beautiful thing about home AP, and that is ...it is an ECO system. It is NOT Aquaculture and it is NOT Hydroponics. It is Aquaponics.
An AP system is an ECO system so therefore must be in a balanced state. This should never be forgotten. Aquaponics as an ECO system is a system for this time in history. More and more folk are realising the importance of growing food using all the natural processes possible. There is increasing rejection of systems that rely on chemicals or push things way beyond natural limits. A balanced ECO system such as Aquaponics allows for the raising of food fish and vegetables in a symbiotic relationship.
The great majority of home system owners, especially those that have purchased a ready made premium kit are not interested in additional complications in running a system. They are very attracted to the beauty of the ECO system. It fits well into their idea/desire to move towards a greener more sustainable lifestyle.
There is an element amongst the AP - DIY world that enjoy tinkering. For those people, build yourself at least one of every kind of filter you can think of and ...enjoy. Tinker away till your heart is contented.
Why not build a replica of the Yellow Polka Dot Filter and attach that to your system?
Please take note, if we were to build a full blown Commercial system we would approach the design with a different set of parameters to produce a commercially viable system while still maintaining the beauty of an Aquaponics ECO system.
Murray Hallam of Practical Aquaponics is available world wide to consult on design and commissioning of commercial scale Aquaponics systems that are efficient in design and maintain the working principle of an ECO system.
PS.... Come to my Commercia and Small Farm Training at Pescadero California December 2 to 6 ....2012. See here for more info about all my training classes in Australia and the USA.